It's been a rough relationship road for Katie and Joey since the start of "Teen Mom 3." Their communication issues have only gotten worse over time, and now, another serious problem is threatening to end things between them for good. On tonight's episode, the newly engaged couple found themselves butting heads over the fact that Joey, despite Katie's pleading, refused to quit smoking pot.

Regardless of a conversation the couple had in which Katie expressed her disapproval of Joey being high around their daughter, Joey simply wasn't interested in breaking his habit. He said he "didn't feel like it," and claimed that his addiction to pot was not at all the same as an addiction to harder drugs. Later on in therapy, Katie revealed that her father has a history with methamphetamine, and even went to jail because of it, so it's no wonder she's so strongly against any drug use in her home. The counselor suggested Joey try sobriety to save their relationship and he begrudgingly agreed, but overcoming addiction normally involves much more than a verbal oath to stop.

So, do you think Joey's drug use could be the final nail in his and Katie's relationship coffin? Take our poll, and sound off in the comments.